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GROUNDCOVER
Issue 129 | July -- August 2017 | GRDC GROUNDCOVERTM SUPPLEMENT
STRATEGIC GRAZING
NO TILL BENEFITS FROM
STRATEGIC USE OF LIVESTOCK KEY MESSAGE
A long-term comparison of no-till, no-burn
against different grazing approaches has
challenged the belief that livestock and
no-till are incompatible.
By Cam Nicholson
n Grazing can provide an additional
income stream for no-till croppers
as well as assisting with weed, pest
and disease management.
No-till farming has historically meant
the exclusion of livestock from cropping
paddocks, but research by the GRDC-
funded Grain & Graze program has found
that gross margins can be substantially
improved with strategic grazing.
An 11-year trial was conducted on a
15.6-hectare paddock at Werneth, in south-
western Victoria, to compare a standard
no-till/no-graze treatment with two
different grazing approaches: a traditional
grazing of stubble and the winter crop
with burning, and a more strategic grazing
with no burning. The paddock was
divided into three equal areas that were
managed separately from 2005 to 2015.
The gross margin (gross income
less enterprise costs) for the strategic
grazing with no burning treatment
was an average of $1348 per year,
substantially ahead of the no-till/
no-graze treatment gross margin of $936
per year (Table 1). The traditional graze
and burn treatment (control) provided
an average annual return of $1183.
Yields fluctuated markedly between
years, with no single treatment consistently
out-yielding another. The most dramatic
fluctuation was in 2010, when the canola
under the no-till/no-graze treatment failed
to establish twice due to unprecedented
slug damage and was not harvested. A wet
summer and retained stubble led to massive
pest problems that could not be controlled
in this treatment despite repeated baiting
(see photo). The canola on both grazing
treatments yielded two tonnes per hectare.
There were several occasions where we
observed higher levels of crop biomass,
especially in the no-till/no-graze treatment,
but this did not lead to greater yields in that
season or the following year. For example,
in 2008, the peas under the no-till/no-graze
treatment grew double the biomass, but
yielded only slightly higher than the other
treatments. We also failed to observe any
nitrogen impact on the following barley crop.
To date, there has been little evidence of
increased soil carbon under no-till cropping
in the high-rainfall zone. However, in
the long-ter m trial fractionated soil
carbon testing in late 2016 showed
more particulate (rapid turnover) and
humic carbon in the no-till treatment
compared to the other treatments
(Figure 1), indicating that removing
grazing can help soil carbon.
There are many different factors to
consider with strategic grazing of a no-till
system. A more comprehensive report
(Comparative analysis of no-till no-grazing to
stubble grazing and burning), including detailed
gross margin analysis, strategic soil, weed,
biological activity and nutrient removal
calculations, will be available on the Grain
& Graze website in July/August. o
FAST FACT
Strategic grazing can provide benefits to
no-till cropping enterprises that lead to
higher profits.
The canola crop in the no-till, no-graze treatment (left) failed despite being sown twice due to
unprecedented slug damage, while the pest pressure in the graze and burn treatment (right) was minimal.
PHOTO: CAM NICHOLSON
SOURCE: CAM NICHOLSON
FIGURE 1 Soil carbon fractions
(0--10cm) for the three di erent
treatments.
Recalcitrant
Carbon in 0--10cm (t/ha)
50
40
30
20
10
0 No till,
no graze Strategic graze,
no burn Graze, burn
(control)
Humic Particulate
GRDC Research Code SFS00028
More information: Cam Nicholson,
Nicon Rural Services, 03 5258 3860,
cam@niconrural.com.au; Grain & Graze,
www.grainandgraze3.com.au
TABLE 1 Cumulative cash position
($/ha) for the three practices with
and without livestock.
Grazing is valued at $0.035/day.
Key measures No till,
no graze
Strategic
graze,
no burn
Graze,
burn
(control)
Crop component
(2005--2015) $10,296 $12,422 $11,068
Crop component
(average annual) $936 $1129 $1006
Livestock value
(2005--2015)
$0 $219 $177
Livestock value
(average annual) $0 $20 $16
Total value
(annual average) $936 $1348 $1183
SOURCE: CAM NICHOLSON